Kalni - Honey, I think the issue right now is not that he cheated on you. You knew all that and still chose to reconcile with him, I think you had plenty of time to process that wound.
I think the issue is you suspect him of not being totally straight about his dealings now - of flirting with that woman from work, and who knows what else? You're afraid he's not behaving the way you would expect him to if he was truly remorseful.